We have about 5 days in south Italy.
Should we stay in Rome and day trip to Pompeii/Capri.
Or should we stay in Sorento and go to Rome for two day trips?
It's about 4 hours to Rome from Sorrento, and visa versa. I'd recommend spending 2-3 nights in Rome, then transfer to Sorrento for 2 or 3 nights, you do the math to decide which is more important.
Day trip to Pompei or Capri is easier from Sorrento and the Amalfi coast is worth 2 or 3 nights.
You'll spend most of your day traveling to get to the start of what you want to do if you try to day trip it from either city.
We fly into Rome, so we will try 3 nights in Rome and 2 in Sorento. Is sorento the best home base in this aria?
then from Sorento we will drive North, see Pizza and then we were thinking of Parma for a day befor going to Venice for two days.
Your itinerary sounds good. Sorrento is definitely the best home base. We absolutely love Sorrento, it's too bad you don't have more time to stay to see and experience more there. From our experience, Rome is 3 hrs by train from Sorrento. Enjoy!
I would love to have been able to spend more time around the Amafli coast, we just had a day trip to Naples/Pompeii from our base in Rome.
If you are staying in Rome and going to Pompeii from there I reccomend spending a little extra and taking the high speed train there. We did that and got there in about 1.5 hours, we took the slower train home.